Effects of Vessel Wall Elasticity on Blood Flow

血管壁弹性对血流的影响

• 批准号: 04670845
• 负责人: SEKI Junji
• 金额: $ 1.34万
• 依托单位: National Cardiovascular Center Research Institute
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-04670845/
• 关键词: Vessel Wall Elasticity; Pulsatile Flow; Turbulence Transition; Laser-Doppler Anemometer; Wave Propagation; Propagation Velocity; Network Architecture; Spontaneous Hypertension; 血管弾性; レーザ・ドップラ流速計; レイノルズ数; Vessel Wall Elasticity; Pulsatile Flow; Turbulence Transition; Laser-Doppler Anemometer; Wave Propagation; Propagation Velocity; Network Architecture; Spontaneous Hypertension; 血管弾性; レーザ・ドップラ流速計; レイノルズ数

In vitro and in vivo experiments were conducted to study the effects of the vessel wall elasticity on the blood flow characteristics focusing on thegeneration and development of blood flow turbulence and on the propagation of flow pulse in microvessels, respectively.In in vitro experiments, a fully developed pulsatile flow (sinusoidal flow in addition to mean flow) was measured by a laser-Doppler anemometer. The velocity waveforms and the velocity profiles in the tube cross-section were obtained under various conditions of pulsatile flow. When the flow was not turbulent, the velodcity waveforms and the velocity proviles agreed well with the theoretical predictions. Regarding the turbulence transition, the centerline velocity was recorded as the mean Reynolds number was increased with a fixed frequency and amplitude of pulsation. The flow became turbulent in the deceleration phase when the mean Reynolds number was larger than a critical value, the transition Reynolds number. The transis … More ion Reynolds number was 2400 at the modulation Reynolds number of 880 and the freqyency parameter of 5.9. Considering the transision Reynolds number of steady flow was 2000, it means that the flow is stabilized under the pulsatile condition.In in vivo experiments, propagation of flow pulse was studied in microvascular networks of rat mesentery by a fiber-optic laser-Doppler anemometer microscope (FLDAM). The mean flow rate, amplitude of the flow pulsation, phase lag of the microvascular flow relative to the carotid arterial pressure were determined in arterioles, capillaries and venules. The arterio-venous distributions of the mean flow, flow amplitude and phase lag were analyzed based on an idealized model of the microvasculature. The difference observed in the distributions between spontaneously hypertensive rats (SHR) and normotensive control rats (WKY) were explained from the theoretical model by the rarefaction of small arterioles in SHR.Thepropagation velocity of flow pulse was also measured in arterioles. The elastic modulus of the vessel wall estimated from the propagation velocitywas in the range from 2x10^6 to 2x10^7 dyn/cm^2, which was in the same order of the elastic modulus for large arteries. Less

In vitro and in vivo experiments were conducted to study the effects of the vessel wall elasticity on the blood flow characteristics focusing on the generation and development of blood flow turbulence and on the propagation of flow pulse in microvessels, respectively.In in vitro experiments, a fully developed pulsatile flow (sinusoidal flow in addition to mean flow) was measured by a laser-Doppler anemometer.在各种脉冲流动条件下，获得了管横截面中的速度波形和速度曲线。当流动不动荡时，速度波形和速度与理论预测良好同意。关于湍流跃迁，将中心线速度记录为固定频率和脉动放大器，因为平均雷诺数增加了。当平均雷诺数大于临界值（过渡雷诺数）时，流量在减速阶段变得湍流。过渡…在880的调制雷诺数上，更多的离子雷诺数为2400，而频率参数为5.9。考虑到稳定流量的转化雷诺数为2000，这意味着在脉动条件下流动稳定。在体内实验中，流动脉冲的传播是通过光纤肠系膜的微血管网络中的，通过光纤 - 充电激光射击器 - 多型仪摩二仪表仪（FLDAM）。基于微脉管系统的理想化模型，分析了平均流量，流动放大器和相位滞后的平均流量，流量脉动的放大器。从理论模型中解释了自发性高血压大鼠（SHR）和正常的控制大鼠（WKY）之间在分布中观察到的差异，该模型通过小arteols在SHR中的稀有范围来解释。在小动脉中，小动物的流量脉冲也被测量。血管壁的弹性模量从2x10^6到2x10^7 dyn/cm^2的范围内估计，该模量的弹性模量与大动脉的弹性模量相同。较少的